Max Levchin, the entrepreneur who helped co-found PayPal (srbay) and Slide, has joined Yahoo’s board of directors. Levchin, a computer scientist and angel investor is part of a welcome change at the stodgy web portal, whose board seemed to regard the role of director as somewhat of a sinecure as opposed to a place where directors rolled up their sleeves and tried to get things done.

CEO Marissa Mayer is slowly making her mark on Yahoo, and the addition today of Levchin to the board can probably be seen as a testament to Mayer’s faith in engineers and entrepreneurs. From the get go, we’ve heard Mayer, who was a former executive at Google, asked for more engineering talent at the beleaguered web portal. Just this last week some of her changes at the product level associated with adding new features to Flickr and other changes are coming to light. Levchin fits right in.

Yahoo had apparently been courting Levchin for a while, and it certainly needs a blast of innovation from someone known in the Valley for being thoughtful and well-versed in developing social startups. For more on Levchin, check out this post from 2010 featuring a video interview Om did with Levchin while he was still at Google.

Levchin also serves as chairman of the boards at Kaggle and Yelp and is a director at Evernote. Yahoo also said that Intuit CEO Brad Smith and Weather Channel CEO David Kenney are stepping down from the board, leaving Yahoo now with 11 directors.